1. Field of the Invention
The present invention relates to a ratchet wrench, and more particularly to a ratchet wrench, wherein the urging spring is supported and guided by the guide shaft of the positioning plate, thereby facilitating operation of the ratchet wrench.
2. Description of the Related Art
A conventional ratchet wrench in accordance with the prior art shown in FIGS. 1 and 2 comprises a handle 10, a drive head 15 mounted on a distal end of the handle 10 and having a first end formed with a receiving hole 16, a mediate portion formed with a receiving recess 17 communicating with the receiving hole 16, and a second end formed with a receiving chamber 18 communicating with the receiving recess 17, a ratchet wheel 20 mounted in the receiving hole 16 of the drive head 15 by a C-shaped snap 22 and having a periphery formed with a plurality of ratchet teeth 21, a pawl member 23 pivotally mounted in the receiving recess 17 of the drive head 15 and having a first side formed with a plurality of engaging teeth 24 engaged with the ratchet teeth 21 of the ratchet wheel 20 and a second side formed with an positioning edge 25, and a control knob 26 rotatably mounted in the receiving chamber 18 of the drive head 15 and formed with a hole 27 for receiving a spring 28 which is biased by an urging pin 29 which is urged on the positioning edge 25 of the pawl member 23 to push the pawl member 23 to press the ratchet wheel 20 to control the drive direction of the ratchet wheel 20. Thus, by rotation of the control knob 26, the ratchet wheel 20 is rotated in one direction only when the drive head 15 is rotated.
However, the conventional ratchet wrench needs a larger space to receive the urging pin 29, thereby increasing the volume of the ratchet wrench efficiently. In addition, the spring 28 is not supported by the control knob 26 efficiently, so that operation of the conventional ratchet wrench is not smooth and conveniently.